Users are increasingly sharing their product interests and experiences with others on e-commerce websites. For example, users can “tag” products using their own words, and these “product tags” then serve as navigation cues for other users who want to search for products. Also, socially endorsed information contributors are sometimes highlighted on websites and serve as direct information sources. This study examines the effects of these two distinct social product search cues, product tags and socially endorsed people, on users’ perceived diagnosticity and serendipity of their product search experience. While product tags support product navigation via a variety of product features tagged by the community, access to socially endorsed people enables users to browse diverse and high-quality alternatives favored by these individuals. We constructed an experimental website using real data from one of the largest social-network-based product-search websites in China to conduct an empirical study. The results o...